what can i do ....??

hmmm, its serious and a very difficult situation for that girl...

first of all, you should tell her that there are other people on this earth who love her and care for her more than that guy e.g. her parents, relatives and friends

so, if not for her own self, she should live for the people who love her

secondly, the best way to come out of this situation is to stop thinking of that guy coz the more you think of negative things, the deeper they go into the mind and it becomes very difficult for the person to come out of depression

thirdly, she should make herself busy so that she never gets time to think of what has happened with her...the following quotation might help her...

"Are you bored with life and want no-more of it? Then throw yourself in some work you believe in with all your heart. Live for it, die for it, and you will find happiness that you had thought could never be yours!"
Dale Carnegie

Fourthly, go to Satsang! Life is not meant to be wasted in love of people who don't care of us. If they don't care for us, may God bless them. But we should not spoil our life. Try to learn the real meaning of life and real meaning can be known only by associating with the wise and reading their words of wisdom!

May God bless her and give her wisdom and strength to come out of this situation!